Hypertrophic pyloric stenosis (ultrasound measurements mnemonic)

Dr Dan J Bell and Dr Bruno Di Muzio et al.

Hypertrophic pyloric stenosis can be characterised in ultrasound studies by the measurements of the hypertrophic muscle. Although the criteria can vary from publication to publication, an easy way to keep in mind those values is remembering the first digits of the number "pi", also represented by the Greek letter "π":

π= 3.1415

  • pyloric muscle thickness, i.e. diame­ter of a single muscular wall on a transverse image >3 mm (most accurate 1)
  • pyloric transverse diameter ≥14 mm
  • length, i.e. longitudinal measurement >15 mm
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Article information

rID: 49722
Section: Mnemonics
Synonyms or Alternate Spellings:

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